In today's passenger aircraft, passengers are allowed to carry small items of goods in transit, so-called hand luggage, with them into the passenger compartment of the aircraft. Due to safety provisions, passengers may stow such hand luggage only underneath the seat in front of them or in an overhead storage device, a so-called overhead bin or hat rack, that has been allocated to them.
During the phase of boarding the aircraft, passengers may store their hand luggage but this often results in extended waiting periods because a passenger blocks the aisle when loading the hat rack, i.e., an overhead baggage compartment, forcing the remaining passengers to wait.
Apart from stowing items of hand luggage of passengers, prior to the boarding phase it is necessary to stow consumable products, for example, drinks for in-flight service. These items are stored in trolleys, and are stored in the aircraft in dedicated locations, namely in the galleys. Loading and unloading trolleys is handled by the ground crew who unload the empty trolleys and load the filled trolleys by way of the aircraft entrances. Among other things, this may prolong the time on the ground during the flight phases of an aircraft.